The Danish Breast Cancer Cooperative Group (DBCG) was established by
the Danish Surgical Society in 1976 with the aim of ensuring optimal diagnostic
procedures and
treatment of breast cancer on a nation-wide basis and thereby to improve the
prognosis.

To achieve
this DBCG has since the beginning of its activities prepared evidence-based
guidelines for the whole country regarding diagnostic procedures
and treatment (surgery, radiotherapy, and systemic therapy). These have
continuously been further developed and evaluated in randomized
trials and quality-control studies.

Already from the start a clinical database was established and the relevant
departments of pathology, surgery, and oncology have since then systematically
reported information about diagnostics, treatment,
and follow-up. From the beginning this reporting happened via standardized data
sheets but from 2009 it has gradually been changed to on-line web-based
reporting.